<!doctype html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport"
        content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>Document</title>
  <style>
    :root, body {
      margin: 0;
      padding: 0;
    }

    .box {
      background: lightblue;
      min-height: 100vh;
    }
  </style>
</head>
<body>
<div id="app">
  <button id="btn">toggle</button>
  <div class="box">
    Lorem ipsum dolor sit amet, consectetur adipisicing elit. Adipisci animi doloremque doloribus dolorum earum esse est
    exercitationem expedita harum laudantium libero, molestias quidem recusandae repellat, reprehenderit sed similique
    ut vel.
  </div>
</div>
</body>
</html>
